(6) Taxes on Income

Earnings before taxes on income and details of the provision for taxes on income for the years ended December 31, 2014, 2013 and 2012 were as follows (in thousands):

	2014		2013		2012
Earnings before taxes on income — United States	$	454,390	$	408,678	$	340,526

Provision for taxes on income:
Federal:
Current	$	81,953	$	41,008	$	41,297
Deferred		72,920		97,586		71,767
State and local		14,909		13,785		14,843
	$	169,782	$	152,379	$	127,907

During the three years ended December 31, 2014, 2013 and 2012, tax benefits related to the exercise of stock options and the issuance of restricted stock that were allocated directly to additional paid-in capital were $6,119,000, $3,001,000 and $3,212,000, respectively.

The Company’s provision for taxes on income varied from the statutory federal income tax rate for the years ended December 31, 2014, 2013 and 2012 due to the following:

	2014			2013			2012
United States income tax statutory rate		35.0	%		35.0	%		35.0	%
State and local taxes, net of federal benefit		2.2			2.2			2.8
Other – net		.2			.1			(.2	)
		37.4	%		37.3	%		37.6	%

The tax effects of temporary differences that give rise to significant portions of the current deferred tax assets and non-current deferred tax assets and liabilities at December 31, 2014 and 2013 were as follows (in thousands):

	2014			2013
Current deferred tax assets:
Compensated absences	$	854		$	782
Allowance for doubtful accounts		3,111			1,927
Insurance accruals		2,858			2,572
Other		3,739			4,177
	$	10,562		$	9,458

Non-current deferred tax assets and liabilities:
Deferred tax assets:
Postretirement health care benefits	$	2,795		$	3,015
Insurance accruals		3,325			2,781
Deferred compensation		10,157			9,526
Unrealized loss on derivative financial instruments		—			51
Unrealized loss on defined benefit plans		34,501			9,379
Operating loss carryforwards		515			5,699
Other		20,687			17,925
		71,980			48,376

Deferred tax liabilities:
Property		(547,388	)		(487,187	)
Deferred state taxes		(49,503	)		(46,798	)
Pension benefits		(11,198	)		(13,063	)
Goodwill and other intangibles		(37,936	)		(26,120	)
Other		(21,724	)		(19,318	)
		(667,749	)		(592,486	)
	$	(595,769	)	$	(544,110	)

The Company has determined that it is more likely than not that all deferred tax assets at December 31, 2014 will be realized, including its operating loss carryforwards of $515,000 that expire in various amounts through 2030.

The Company or one of its subsidiaries files income tax returns in the United States federal jurisdiction and various state jurisdictions. The Company is currently open to audit under the statute of limitations by the Internal Revenue Service for the 2011 through 2013 tax years. With few exceptions, the Company and its subsidiaries’ state income tax returns are open to audit under the statute of limitations for the 2008 through 2013 tax years.

As of December 31, 2014, the Company has provided a liability of $1,477,000 for unrecognized tax benefits related to various income tax issues which includes interest and penalties. The amount that would impact the Company’s effective tax rate, if recognized, is $998,000, with the difference between the total amount of unrecognized tax benefits and the amount that would impact the effective tax rate being primarily related to the federal tax benefit of state income tax items. It is not reasonably possible to determine if the liability for unrecognized tax benefits will significantly change prior to December 31, 2015 due to the uncertainty of possible examination results.

A reconciliation of the beginning and ending amount of the liability for unrecognized tax benefits for the years ended December 31, 2014, 2013 and 2012, is as follows (in thousands):

	2014			2013			2012
Balance at beginning of year	$	949		$	1,045		$	1,532
Additions based on tax positions related to the current year		470			239			165
Additions for tax positions of prior years		39			114			53
Reductions for tax positions of prior years		(287	)		(413	)		(502	)
Settlements		—			(36	)		(203	)
Balance at end of year	$	1,171		$	949		$	1,045

The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for federal and state income taxes. The Company recognized net expense (credit) of $40,000, $(421,000) and $(43,000) in interest and penalties for the years ended December 31, 2014, 2013 and 2012, respectively. The Company had $306,000, $266,000 and $790,000 of accrued liabilities for the payment of interest and penalties at December 31, 2014, 2013 and 2012, respectively.